An actor comes to a space every day and sits in a box on the floor. The audience is invited to watch after the actor is in the box. There is a red light bulb atop the box. The bulb turns on at exactly the same time every night. It can only be controlled from inside the box. After one minute the light turns off and the audience is free to leave.
Imagine that next door is a second, identical theater. Here is precisely the same set-up, except that there is no actor. Still, both boxes illuminate at the same time; in fact the two lights are on the same circuit. Finally, neither the actor nor audiences can differentiate the two spaces: the chance of an actor in one certain space is 1 in 2. How many performances take place on a single night?